red and blue vein blood cells anatomy human vascular system leukocytes erythrocytes platelets icon biology medicine

vector flat background human anatomy icon health healthy healthcare disease medicine care anatomical cartoon sign symbol clinic science diagnostic patient treatment system illustration education biology emblem internal medical artery vein blood structure vessel circulatory blue red cardiology cell macro micro thrombosis physiology platelet cells erythrocytes erythrocyte hemocytes leukocyte leukocytes thrombocyte